HID: wacom: generic: support touch on/off softkey

Wacom Cintiq Pro has a softkey to turn touch on/off. Since it is
a softkey, hardware/firmware still reports touch events no matter
what state the softkey is. We need to ignore touch events when
the key is in off mode.

Signed-off-by: Ping Cheng <ping.cheng@wacom.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Tested-by: Aaron Armstrong Skomra <aaron.skomra@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index 9aec5b3..037b9c0 100644
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -2100,8 +2100,10 @@ static void wacom_set_shared_values(struct wacom_wac *wacom_wac)
 		wacom_wac->shared->touch_input = wacom_wac->touch_input;
 	}
 
-	if (wacom_wac->has_mute_touch_switch)
+	if (wacom_wac->has_mute_touch_switch) {
 		wacom_wac->shared->has_mute_touch_switch = true;
+		wacom_wac->shared->is_touch_on = true;
+	}
 
 	if (wacom_wac->shared->has_mute_touch_switch &&
 	    wacom_wac->shared->touch_input) {